Proposal of delamination strength evaluation method of thermal barrier coatings based on interface cohesive model with interface oxidation process
Proposal of delamination strength evaluation method of thermal barrier coatings based on interface cohesive model with interface oxidation process
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基于界面内聚模型和界面氧化过程的热障涂层剥离强度评价方法的提出
DOI：
10.2472/jsms.53.459
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发表时间：
2004
期刊：
影响因子：
--
通讯作者：
M. Arai
中科院分区：
文献类型：
--
作者：
M. Arai
在“热障涂层（TBC）”中，陶瓷顶涂层和金属粘结涂层之间的热生长氧化物层的形成已知会导致界面内聚力的降低。这种内聚性降低实际上与严重的损坏相关联，例如由于热循环、长时间等温暴露和热机械疲劳引起的涂层剥落。界面裂纹力学已被广泛用于评估这种界面强度。在力学中，由于应力场求解的数学处理比较困难，一般只考虑理想的界面条件。然而，实际界面强度主要受Al扩散过程引起的界面氧化生长效应和界面固有问题（如界面几何形状呈波浪形）的影响.在本研究中，界面内聚模型，它是基于顶部涂层和基体之间的界面节点之间的弹簧连接，被开发用于评估TBC界面分层强度，考虑涂层固有特性，例如热生长氧化物形成。所开发的模型的TBC分层测试的四点弯曲的有限元分析的应用。此外，脱层能量，这是定义的能量存储在界面弹簧，直到界面断裂面形成，新提出的TBC脱层强度。
Thermally grown oxide layer formation between ceramic top coating layer and metal bond coating layer in “Thermal Barrier Coating (TBC)” is known to cause reduction of interface cohesion. This cohesion reduction is practically associated with a serious damage such as coating spallation due to thermal cycling, prolonged isothermal exposure and thermo-mechanical fatigue. Interface crack mechanics have been used widely to evaluate such interface strength. In the mechanics, an ideal interface condition was considered, because of the difficulty of mathematic treatment for stress field solution. However, actual interface strength is predominated by the effect of interface oxidation growth by Al diffusion process and interface instinctive problem such as a wavy interface geometry.In this study, the interface cohesive model, which is based on a spring connection between the interface nodes in the top coating and the substrate, is developed for evaluating TBC interface delamination strength with taking into account coating instinctive characterization, such as thermally grown oxide formation. Application of finite element analysis included with the developed model to the TBC delamination test by four-point bending is shown. Also, delamination energy, which is defined by energy stored in the interface spring until interface fracture surface formation, is proposed newly as TBC delamination strength.